The Ghostbusters may have been the go-to guys for spookhunting in the '80s, but if weird shit was going down in your neighbourhood during the '90s, there was only one number to call: that connecting you to a basement office in the J. Edgar Hoover Building, Washington, DC. From there, FBI agents Fox Mulder and Dana Scully pursued cases with a paranormal tinge, encountering everything from ghouls to killer cockroaches in their quest for 'the truth'.

Guided by the hand of creator Chris Carter, The X-Files fused lurid horror and sci-fi plotlines with detailed procedural, making even its most outre events seem credible. The approach paid huge dividends, turning the Fox TV series first into a cult smash, then a mainstream phenomenon. But would it have been half the hit it was without its lead duo, David Duchovny and Gillian Anderson? Doubtful.

Individually, they're charming -- Duchovny laid-back and appealingly goofy; Anderson smouldering and smart. But together they're dynamite, especially within the dynamic established by The X-Files, casting the former as a boyishly enthusiastic believer in the supernatural and the latter as his ever-sceptical foil. Would they manage to stop a government conspiracy to hand over Earth to aliens? And, more importantly, would they end up as an item?

The final season ended in 2002 without definitely answering either question. It was a dark time for X-philes, as a lawsuit between Carter and Fox prevented a second big-screen outing (after 1998's Fight The Future) and Duchovny and Anderson went off to try new things. For him, passion project House Of D and the lead in raunchy TV drama Californication. For her, roles in The Last King Of Scotland, A Cock And Bull Story and erotic thriller Straightheads, which climaxes with Anderson ramming a shotgun up someone's bottom.

But for most of a decade, fans kept the faith and clamoured for The X-Files to be reopened. And this year, finally, their prayers were answered. His lawsuit resolved, Carter summoned his old cast and crew to Vancouver, the show's spiritual home, to shoot a mystery that promises to be one of Mulder and Scully's spookiest yet.

Empire's Acting News Editor Nick de Semlyen met with the two stars shortly after the film wrapped. "Despite a tough shoot in the icy wilds of Canada, the pair were on great form and clearly happy to be back together," says de Semlyen. "In person they're nothing like their X-Files alter agos, bantering bawdily on subjects as random as poltergeists, porn and Jeff Goldblum. It made for a fun, enjoyably unpredictable inerview -- I certainly didn't expect to be confronted with Duchovny's testicles at the midway point..."

So, what's it been like pinning on your FBI badges again?

GA: It's been good. But hard work. It's been a long time since I've done such a long shoot Š I've chosen things between three and six weeks, and this has been the first time for ages that I've done two-and-a-half months. David has a lot of physical stuff to do in the film, and I feel like on the one hand I've gotten off easy and on the other hand I'm still exhausted. I just feel old. (Laughs)

DD: I did a lot of running for this movie. You know, action is pretty boring to do as an actor. Action and sex scenes are silly because it's all faking. I mean, it's all fake, but those things are faker than the rest. Chris wanted a scene where I chase someone as fast as I can for five minutes. I will be interested to see how it cuts together, but we sure ran our asses off for, like, five or six nights in a row, in the rain. It was pretty stupid, and I hated it.

GA: The shoot was pretty gruelling on everyone. The cold, the long nights... some of the crew were saying it was the hardest one they'd ever done. I got pretty sick, and at one point my son had scratched my cornea, so I was doing shots with a red eye and snot coming out of my nose. Look out for those ones.

How about the hair? You don't particularly like being a redhead, do you?

GA: No, I don't. It was a bit shocking for me at the beginning, because shortly after the series ended I got rid of the red as quickly as possible, to try to keep some semblance of privacy. All of a sudden in public, people have started paying a little more attention and noticing my presence more. I'm not crazy about that. At some point I'm going to go back to blonde, but just in case there are any reshoots I'm keeping it like this -- it took nearly twenty hours to get it back to this colour and I don't want to repeat the process.

What's your natural hair colour?

GA: Not red, but not blonde either. Somewhere in between.

DD: She's bald. Completely bald.

GA: Hey! It's funny because when we did the pilot it was kind of a mousey brown, and suddenly there was an executive directive -- I don't know from whom -- to make it red. My mole has also been an issue. Chris decided there wasn't room on my face for it, much to the chagrin of years of make-up artists having to go in and cover it up.

Was it easy for you to slip back into Mulder and Scully mode?

DD: I figured it would be easy because in some ways I don't feel like I ever stopped making the show. Then, after the first day of doing all that running, I thought, 'Jeez, I don't really know what I'm doing. I've got to buckle down here a little bit.'

GA: I had a particularly difficult, emotional scene to do over my first two days and I would have paid a lot of money not to have to have done it then. The problem was a mixture of exhaustion, because I'd just flown in from India via London, and assuming it was going to be really easy to step back into Scully's shoes. That wasn't the case. Doing the scene I was internally rebelling against it, thinking, 'There's gotta be a way out of this...'

DD: Gillian is tenacious, though.

GA: Thank you. (Laughs)

Is it true this film has a horror vibe to it?

DD: I'd liken it to Tooms (a Season 1 classic about a stretchy serial killer), which is also in the horror/thriller model. Chris has a lot of experience in implying horrible things more than showing them. That said, with this new movie, I definitely know we shot graphic stuff that can't be in the theatrical version. Will it go on the DVD? He might have plans for it. I don't know.

Way back before The X-Files came into your lives, each of you forayed into the world of soft-core porn. What are your memories of that?

DD: Ah yes, The Red Shoe Diaries. It's funny because that's been on TV a lot here in Vancouver while we've been shooting this. It's always on at three in the morning in Canada. And people like it. They come up to me and ask if there's going to be any more, and I haven't shot any of it since '94 or '95.

GA: I've still never seen an episode of that.

DD: I actually have a fond spot in my heart for the whole thing because [creator] Zalman King was very good to me. He tried to help me as an actor and it was just a good experience to be in front of the camera. And in terms of the soft-porn thing, I really wasn't in any of the kinky scenes. I was always monologuing while wandering around with a dog, so I was left out of the fun. Whereas I am fully naked for a single frame of New Year's Day, my first movie. But not intentionally -- it just happened. I mean, I knew I was naked, but didn't know I was swinging about on camera for a second.

GA: The first on-camera thing I ever did was this lame little film called The Turning that they recently tried to re-release on DVD as a porn. There's one scene in a kitchen where I make out with a boy and afterwards it's clear we've had sex or whatever. The number of times people bring up that fucking scene... even the kids of some friends of mine had it downloaded on their computer!

Are those the things you're most embarrassed about now?

DD: Those and the photoshoots.

GA: (Laughs) Yeah, I'd have to agree. I did one, I think it was for People magazine -- you know how cheesy some of their photos are -- and I actually refuse now to do People. But I had just had my daughter, so there was this shot of me lying on our dining-room table in my wedding dress with my breastfeeding tit just exposed to the world. And it was a time when my hair was really, really bad in the series, and it was equally bad for this shoot. I think there was another shot and me and my then-husband in (daughter) Piper-s room holding a teddy bear. There was even talk at one point of us getting in the crib. So embarrassing! (Pause) You should ask David about his teacup picture...

DD: That's so weird -- someone just sent me that shot on my phone a couple of hours ago, saying 'Is that you?' And I hadn't seen it in I don't know how long. It was taken right when we started doing The X-Files, when I went down to LA to do a bunch of shots at my manager's house. In between set-ups I was just fucking around, naked, and I put this teacup over my genitals. And they took a couple of pictures, just for us, for a laugh. I was innocent, thinking, 'ItÕs my balls. Who's going to possibly want a picture of my balls?' And a couple of years later my then-publicist, who will remain nameless, sold them. Here, look... (He pulls out his iPhone and, after a rapid bit of button-toggling, displays the photo. Empire gives it a brief, polite glance. Anderson erupts into giggles.)

GA: Oh God! I remember during the series you were really embarrassed you'd ever done that. You look so young in it!

DD: (Putting phone away) And that's all you get...

GA: Those are the things you do when you're younger and you think everybody does that, or someone older than you convinces you it's okay. And years later you think, 'Oh my God!' Two years later, sometimes...

The X-Files first started production in 1993, when you, David, were 33 and you, Gillian, 25. Do you remember meeting each other for the first time?

DD: Yeah. It was at the network reading for the pilot. There were two actors -- me and another guy -- and four or five girls. And just by chance I sat down next to Gillian and said, 'Do you want to read through the lines?'

GA: I remember it a little differently. The first time I met David was outside in the hallway at that reading, and he was quite charming and picking up all the girls passing by. (Both laugh) Someone had said I should watch Kalifornia before I auditioned, but I never got round to it.

By its second year, the show had exploded into a cultural phenomenon. With that success came fame and riches, but also, I'm guessing, some truly weird fans...

GA: You guess right. It's letters mostly. There are different groups. There are the obsessed fans who purely base their lives around the series and have our faces tattooed on their butt-cheeks. Then there are the fans who are mentally unstable. And those are two very different categories.

DD: My weirdest experience happened last year, just before The TV Set came out, when I was down in Vegas doing a conference on independent film. I was waiting backstage for my car to take me to the airport, because I can't get out of Vegas fast enough. And this couple, a guy and a woman, were hanging back, looking at me nervously, and I thought, 'Okay, these two are going to make an approach.' Sure enough, the guy comes over and says, 'My girlfriend is a really big fan.' I thought, 'Oh my God, these guys want to swing. They live in Vegas and he wants to watch me do his wife.' And he goes, 'I want to ask you something... will you ask her to marry me?' The question was so weird it took a while to process -- I was like, 'You want me to ask her to marry me?' But I finally worked it out, did it properly and everyone there was crying. I kind of enjoyed that.

GA: The pair of you battled aliens, vampires, mud-monsters and maggot-men together for eight seasons. Then, David, you slowly phased yourself out of the show. Had you become disillusioned with it?

DD: Disillusioned is the wrong word. It was more like creative fatigue. Fatigue in general of doing a show, not with the character or the franchise or Chris or Gillian. X-Files took ten months of the year to film, whereas, say, Californication takes only three -- I can do that indefinitely. So coming back to it now is not going against any feeling I ever had. This [movie] being only a three-or-four month commitment, it's actually a pleasure to come back and do it. If you said, 'Go back and do the series again,' I would never do that, but to work with these people for a four-month period every three years or so? That would be a great thing to happen.

Did you follow the show when you weren't in it?

DD: I'm sure I watched it a few times. I wouldn't say I followed it...

A lot of fans were unhappy with the way it ended, which was, it has to be said, with a whimper rather than a bang. Do you concede that they have a point?

GA: You know what? By the time it was done I couldn't even have a conversation about it. I don't have enough of a perspective to say whether questions were answered or whether it was all wrapped up, and honestly, there's part of me that doesn't care. I'm sympathetic to die-hard fans who might feel left in short shrift, but...

DD: We did get bogged down a little in the details of the mythology or what-have-you. What I like about this new film is that it's lean, fast-moving and focused. It's like one of the classic episodes from the first couple of seasons.

Do you both have lots of X-Files memorabilia knocking about at home?

GA: I've got huge tubs full of stuff I can sell on eBay. If there are people out there that are interested, I want them to come my way and buy my jackets and hats and scripts that are signed by everybody.

DD: I don't have that much stuff. I have some memorabilia I kind of took by mistake. I have slates from shows I directed.

GA: My favourite prop from the show is my tombstone (from the Season 2 storyline in which Scully is abducted by aliens and presumed dead). That's at the end of my office in London.

Doing genre work for this length of time, are you now sick of all things sci-fi?

DD: Depends on the movie. Alien is a great movie. So is Close Encounters. But I'm not the guy who goes out to the science-fiction festival. 2001's good.

GA: I'm a massive fan of Sunshine. Oh my God, I love that film. I've seen sci-fi films and enjoyed them -- though I'm not a big horror fan. Close Encounters is timeless, obviously. But Sunshine, I just love that film. They did an amazing job with it.

David, you urinate on a poster of Independence Day in the first X-Files movie, a kind of territorial in-joke. Did you ever get an irate call from Jeff Goldblum about that?

DD: (Laughs) Jeff's more likely to be mad about my impersonation of him (on one of Saturday Night Live's Celebrity Jeopardy skits). But no, we never heard anything. And I think they made more money than us, so they had the last laugh.

Which jobs outside The X-Files have you found the most fun?

GA: I just had a good time on How To Lose Friends And Alienate People with Simon Pegg. I met Simon a few years ago at a pub quiz and he gave me a videotape of Spaced. It was on PAL, though, so I couldn't watch it. I think he was a bit embarrassed about my 'cameo' in it (in which Pegg's character knocks one off over a poster of Anderson). He doesn't like being reminded!

DD:The Larry Sanders Show was pure enjoyment for me, because I was a huge fan of the show and just an admirer of Garry (Shandling)'s skill as a comedian. He showed me the box set recently and there are clips that are tilling the same soil as Entourage, 30 Rock, those kinds of shows, and yet only Garry's show is both completely real and completely funny. Anyway, I did one episode and got to know Garry a little bit -- we became friends and still are -- and I said, 'I loved doing this. Let me come back and have a crush on you.' And he said, 'ThatÕs fun.' I sat in my X-Files trailer up in Vancouver doing a table-read over the phone speaker. So we did that episode, had fun with that, and then I came into L.A. for the Golden Globes and was staying at the Four Seasons. Tea (Leoni, Duchovny's wife) and I were up in the hotel room and Garry came by. I was in my robe and said, 'It would be funny if I did the Sharon Stone thing to you,' and that's how the Basic Instinct parody (the last ever episode) came about.

Gillian, you've played an exaggerated version of yourself too, in A Cock And Bull Story. Do you both find people still have misconceptions about you?

GA: People always ask if I was really voted Most Bizarre Girl in high school. But that one's actually true. I was living in Michigan in a very conservative town and had a nose-ring and a shaved head and did kind of strange things. (Laughs)

DD: You do hear some strange rumours floating around. One I've heard just this year is that I'm allergic to metal.

GA: Metal? Seriously? That sounds like an X-File.

DD: It also sounds like something it would be extremely difficult to maintain a normal lifestyle with. I couldn't get in a car, couldn't get in a plane, couldn't have my fillings. It would suck.

As Mulder and Scully, you're pretty much fearless. Are you scared of anything in real life?

DD: I'm not a big fan of the clown. And I don't like the idea of being eaten by a shark. I like to swim in the ocean and I think much more about sharks than anyone should. I really resent the fact that my oceangoing experiences are ruined by Jaws.

GA: I'm actually very scared of sharks too. I wanted to be a marine biologist when I was young, which may not have been compatible with that fear.

DD: Really? I wanted to be an archaeologist.

GA: Me too! I didn't know that about you. Except I wanted to do underwater excavation. I probably saw Indiana Jones and then some sea anemones, and wanted the best of both worlds. (Pauses) There's a big part of me that would love to be a secret agent. But if I showed up to do an investigation and interrogate someone now, they wouldn't be able to take me seriously. I've ruined that for myself.

Did you have any other childhood ambitions?

DD: A bath tub, apparently, was the first thing I wanted to be.

GA: Are you serious? (Laughs)

DD: Yeah, my father said I wanted to be a bath tub. After that came the archaeology -- I was in love with the dinosaurs. And then I wanted to be an astronaut at some point. Then a basketball player.

You settled for movie star...

DD: I'm actually thinking about getting back to being a bath tub. I don't think anyone's ever quite segued into that.

Have either of you had a bona fide supernatural experience?

GA: I have felt presences before in buildings. Creepy... stuff. I was in South Africa once, sitting on some people's porch, and I went into this old house and there was something there. The first thing out of my mouth was, 'Have you got a ghost?' and they immediately turned white and said, 'Yes, how did you know?' That kind of stuff. I'm a lot less sceptical in real life than David is.

DD: I don't discount belief. I just discount most of the things people believe in. Having said that, with aliens, for example, it seems unlikely that we're alone in the universe. Yet I'm pretty sure nobody's hiding any contract. It's a ludicrous idea that the government is able to withhold information when they can't even have gay sex in a bathroom without getting found out (Republican Senator Larry Craig was arrested in June 2007 for lewd conduct in an airport toilet).

Aside from the micro-detailed conspiracy arc and scary one-off tales, The X-Files had a lot of comedy episodes. The two of you obviously spark off each other well. Did you ever think up nicknames?

DD: For each other? Well, (regular series director) Rob Bowman calls me Double D. But no, I don't think we ever did. (To Anderson) I'll have to come up with one for you.

GA: I used to call myself Scullbag, but I don't think you ever referred to me as that.

DD: I do remember that whenever we had to do a shot over my shoulder to Scully, that was called an Over-The-Shoulder-Mulder-Holder.

What's your favourite thing about each other?

DD: Gillian just doesn't give up. If a scene's not working for whatever reason, whereas I might go, 'Fuck it, let's just move on,' she won't give up, no matter how tired or frustrated everyone is... sheÕll hang in there 'til we get it right.

GA: My favourite thing about David? The tea-cup. (Both laugh) The easiest answer, I guess, is his sense of humour. He's always looking at the funny side of things, especially when he's around other actors who are comedians or funny themselves -- it can turn into a bit of a contest to see who does the best impressions and such. But aside from there, there's a gentleness inside him that comes out every once in a while that is quite disarming and lovely. It's rare, but very nice.

What's it been like working together again?

GA: It's been good. We slipped back into it very easily and it felt like coming together again with a friend. There were a couple of times when we were filming and we'd look over at each other and go, 'Oh! It's Mulder and Scully!' It was bizarre and wonderful.

Would you like to work together in something unrelated to The X-Files?

DD: Well, Gillian's got that strong English accent she likes to bust out all the time, so maybe we could do a Jane Austen movie or something. I could learn from the master of the Americanised English accent. (Laughs)

GA: We could always go back to the archaeology thing and go on a dig together. Although we kind of did that already, on the series. We've had to dig a lot of stuff up over the years.

And finally, if you had to pick a favourite X-Files moment, what would it be? You're not allowed to plug the new film.

DD: I always go back to the episode Chris wrote and directed that was black-and-white and a homage to Mask (The Post-Modern Prometheus). At the end I slow-dance with Gillian to Cher's version of Walking In Memphis. It's very romantic and nice.

GA: You know, it all kind of gets jumbled up in my mind, but just recently, during this shoot, someone pulled David and I aside to this computer and showed us some clips, on YouTube, that a fan had put together of us in various scenes. And there was an amazing amount of care and intimacy that I'd forgotten about. I mean, people always say we never kiss on the show -- we kissed, like, thousands of times! There are kisses all over the place. There was a level of real intimacy between these two characters, the kind of care that you don't see very much in the real world. I missed that -- and when we saw it again that day, we were totally mesmerised by it.